Accounts Receivable, net - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Write-offs of accounts receivable	$ 400	$ 500
Increase in bad debt expense	805	303
Restaurant/Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowances for doubtful accounts	$ 1,300	$ 900